Cable Loss Research Articles

Measurement of the Tension Loss in a Cable Traveling Over a Pulley, for Low-Speed Applications

BackgroundWire ropes or cables are widely used solutions for force transmission in several industrial applications. Their hysteretic behavior may significantly influence control accuracy or the force transmission’s efficiency. Cables traveling through sheaves can suffer a relatively high tension loss, which this article addresses.ObjectiveThis paper aims to present a simple measurement method for the tension loss in cables traveling over sheaves on bearings.MethodsThe presented measurement method uses a cable-pulley system with a spring installed at one cable end. The pulley is moved in a zig-zag pattern. The force is measured on both cable ends; this way, the tension loss can be determined as a function of the cable tension. The force was measured with S-type load cells, which are highly sensitive to off-axis loads; this problem can be overcome by proving that the force measurement has a proportional error, which can be eliminated from the frictional coefficient. The measurements are compared to two models from the literature; one approximates the power loss of a cable drive by calculating the work of the cable’s inner friction, and the other is a cable bending model, which is used to determine the hysteretic energy of the cyclic bending.ResultsThe result of the measurement evaluation is a coefficient of tension loss that contains the loss coming from the cable bending and the bearing friction. Four cable types and a steel strip with negligible bending hysteresis were measured, the latter for control measurement. It is demonstrated that a significant part of the tension loss originates from the inner friction of the cable and that it is equal to the hysteretic energy of the cyclic bending.ConclusionThe presented method provides a robust measurement for the tension loss factor in cables traveling over pulleys. It is proven that the off-axis loads cause a proportional error in the force measured by S-type load cells, and this measurement error can be eliminated from the tension loss factor. The results demonstrated that the presented models can be used to predict the tension loss in cables traveling over sheaves.

A bi‐level optimization model and improved algorithm for wind farm layout

AbstractWind farm can obtain the maximize profit by optimizing micro‐locations and cables. The factors that affect profit include the power output of wind turbines, cost and et al., where power output is affected by wake effect, cable cost is related to the length and type of collector cable. The profit is calculated on the premise that the costs and power loss of collector cable are determined. Obviously, there is a hierarchical relationship between the above problems. Therefore, a bi‐level optimization model with constraints is constructed in this paper, where the upper‐level objective function is the maximum profit, and the lower‐level objective functions are consists of minimum the cable cost and the power loss of collector cable; Moreover, an improved algorithm (IDEDA), based on differential evolution and Dijkstra, is used to optimize above model; Finally, simulation experiments are carried out for IDEDA and four algorithms for two different wind conditions, and the results show that IDEDA performs better compared to the other four algorithms in terms of profit and cable cost.

Optimal reactive power dispatch with renewable energy sources using hybrid whale and sine cosine optimization algorithm

The optimization of reactive power dispatch entails the complex challenge of controlling and managing the flow of reactive power in power networks to maintain desired voltage levels across many buses. Nowadays, there is a rising preference for employing renewable energy sources rather than traditional thermal generators. This change presents both challenges and possibilities for power system operators and managers. This paper addresses the Optimal Reactive Power Dispatch (ORPD) problem by presenting a novel approach that incorporates solar and wind power plants into existing power networks using the Hybrid Whale and Sine Cosine Optimisation Algorithm (HWSCOA). Solar and wind power plants are established at bus 5 and bus 8 respectively to replace traditional thermal generators in a specific case study using the IEEE 30-bus system. To handle uncertainties associated with load demand changes and the intermittent nature of renewable energy generation, the study employs probability density functions and a variety of scenarios. The primary goal is to minimize power losses in transmission cables while also lowering voltage changes throughout the network. To address uncertainty in load demands and renewable energy output, a scenario-based methodology is used, generating 30 different scenarios to cover all conceivable outcomes. By presenting the ORPD challenge as an optimization problem, the study hopes to achieve considerable reductions in power losses and voltage variations from nominal levels. The findings of this study reveal encouraging results, including significant reductions in power losses and optimized voltage stability even under shifting conditions.

An Experimental Assessment of the Performance of Solar Panels Using Efficiency Enhancement Techniques in India's Tropical Region

<p style="text-align:justify"><span style="font-size:11pt"><span style="line-height:normal"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="font-size:10.0pt"><span style="color:black">Due to its abundance and lack of pollution, solar energy will soon be the most popular source of electricity production. Numerous factors, including the temperature effect, solar irradiance effect, shadow effect, incident angle effect, dust accumulation on the solar cell, shunt resistance, types of solar cell materials, mechanical defects in the solar panel, spectral mismatch loss, cable loss, maintenance and cleaning cycle, load mismatching effect, etc., harm the efficiency of solar P.V. power generation systems. This study aims to quantify the impact of these factors and explore efficiency enhancement techniques to mitigate their effects. Among the various factors, solar irradiation and temperature significantly influence solar P.V. panel efficiency. This research investigates the effects of solar irradiation, incident angle, and temperature through simulations and experimental methods using two 100W solar panels. Efficiency enhancement techniques like sensor-based sun tracking and temperature cooling systems are incorporated with conventional solar P.V. power generation systems. The experimental results prove that the efficiency enhancement techniques improved the efficiency of solar panels by up to 12% compared to conventional solar panels.</span></span></span></span></span></p>

Investigation of Gamma-Induced Changes to Screening Currents and AC Losses in Mono- Versus Multi-filamentary REBCO Coated Conductors Using DC and AC Magnetometry

REBCO (rare-earth barium copper oxide) coated conductor tapes are a highly attractive option for magnet materials in future tokamak fusion power plants. However, the threat of intense neutron and gamma radiation, together with AC losses during magnet coil ramping, has raised concerns around magnet coil lifetimes. Irradiation-induced changes to flux creep rate has been identified as a key performance-limiting factor in REBCO tapes at low temperatures and high fields post-irradiation with gamma rays; spontaneous flux creep contributes to hysteretic AC loss in REBCO cables under applied AC fields. Knowing that multi-filamentary tapes are under consideration for tokamaks as an AC loss mitigation, magnetic measurements and gamma irradiation experiments are presented here on striated and mono-filamentary YBCO tapes to investigate the differences in post-irradiation screening currents and AC losses. Reduction in AC losses improved magnetisation critical current density (Jc) retention after 1 MGy in the multi- relative to the mono-filamentary samples. After the 5 MGy dose, striations then made the multi-filamentary tape more susceptible to Jc degradation because of the thinner individual filament width. Scanning transmission electron microscopy analysis on an analogous GdYBCO mono-filamentary tape did not indicate the introduction of nm-scale amorphisation to the active GdYBCO layer after gamma irradiation. A potential theoretical explanation for the underlying mechanism altering the flux-pinning landscape across the REBCO layer surface in gamma-irradiated tapes is discussed. This work concluded that gamma effects on screening current capability should be considered in future tokamak REBCO tape qualification studies.

Analysis of Magnetization Losses of Twisted Stacked-Tape Cables With Striated Strands

Analysis of Magnetization Losses of Twisted Stacked-Tape Cables With Striated Strands

Experimental and Numerical Study on the Transport AC Loss of Bent CORC Cables

Experimental and Numerical Study on the Transport AC Loss of Bent CORC Cables

Monitoring and Analysis of Prestress Loss in Prestressed Box Girder Bridges Strengthened with External Prestressing.

To investigate the effects of long-term prestress loss on concrete box girders strengthened with external prestressing, a large-span box girder, in service for over 20 years and strengthened with external prestressing, was monitored for four months. Prestress loss in the longitudinal, vertical, and transverse directions of the box girder was calculated according to Chinese code requirements. Magnetic flux rope force transducers were used to monitor the prestress loss in the external prestressing cables. Fiber Bragg Grating (FBG) sensors were used to monitor deflection changes at the mid-span of the bridge. Finally, the effect of prestress loss in the longitudinal, vertical, and transverse tendons on mid-span deflection was investigated through simulations using ABAQUS software. The results show that instantaneous prestress loss accounts for most of the total loss compared to long-term loss, and that longitudinal prestress loss has the most significant effect on mid-span deflection. The impact of longitudinal prestress loss on deflection before and after strengthening was also compared. The downward deflection and up-ward arch caused by longitudinal tendon prestress loss were reduced after strengthening, con-firming the effectiveness of the external prestressing method.

Enhancing Solar Photovoltaic Panel Performance in India's Tropical Climate: An Experimental Study on the Influential Effects of Optical Filters

<p>Due to the increasing global energy demand and consequent climate change from burning fossil fuels, researchers are getting more focused on renewable energies as a potential solution to the world's energy problems. Solar energy is a prominent form of sustainable energy. The solar photovoltaic power generation system’s electrical performance is negatively influenced by several factors, including the impact of solar irradiance, incident angle, temperature, dust accumulation on the top of the solar cell, cracks in the solar panel, shadowing, shunt resistance, solar cell materials, load mismatch, maintenance and cleaning schedule, spectral mismatch loss, and cable loss. The direct environmental factors that have the biggest impact on efficiency are the effects of sun irradiance and temperature. This empirical investigation examined the impact of optical filters on the electrical efficiency of a 40W polycrystalline solar PV panel in India while considering real-time ambient conditions. Through the utilization of an optical filter, the solar PV panel's temperature is diminished, hence enhancing the output power of the solar panel. Based on the experimental findings, the utilization of a transparent plexiglass sheet equipped with a coolant system installed on the solar panels leads to a drop in the average operating temperature of the solar PV module by up to 6°C. Additionally, the output power is enhanced by up to 10W in comparison to the reference solar panel’s output performance.</p>

Enhancement of the underground cable current capacity by using nano‐dielectrics

AbstractIn most underground power cables, cross‐linked polyethylene (XLPE) is utilized as the main insulating material, while polyvinyl chloride (PVC) is usually used as a nonmetallic sheath or jacketing for the cable. Accordingly, improving the electrical and thermal characteristics of these materials leads to an increase in cable dielectric strength, besides a rise in the current capacity of the underground power cables. Thus, enhancing the thermal characteristics of cable insulation is the goal of many research studies. In this regard, increasing the current capacity of underground power cables is an essential topic for electrical distribution and transmission networks. This usually occurs by increasing the cross‐sectional area of the cable conductor, which means raising the cost of transmitting electrical energy. Another proposed alternative may be to improve the thermal properties of the dielectric material using nanotechnology to allow better dissipation of heat resulting from the cable losses. This article proposes the use of nano‐composite dielectrics to increase the current capacities of underground power cables. Nano‐fillers are used to enhance the thermal and electrical characteristics of XLPE and PVC, which represent cable dielectric materials. Accordingly, in this paper, many experiments are conducted on various nano‐dielectric materials to choose the most appropriate nano‐dielectrics for improving both the thermal and electrical properties. Hence, measurements are performed on the thermal and electrical properties of dielectric nano‐materials manufactured in the laboratory. Further, calculations of the cable's current capacities by the use of the measured properties of nano‐dielectrics are done considering several backfill soils. From the obtained measurements and calculations carried out on cable capacities, it is concluded that the use of XLPE/ZnO 5 wt.% as the insulation and PVC/ZnO 5 wt.% as the jacket material increased the cable current capacity by 6.2% for a cable of 33 kV rating, 9.2% for 66 kV cable, and 15.7% for 220 kV cable when wet clay is used as backfill soil. From the calculations carried out it is found that the use of nano‐composite dielectrics reduces the temperature of the cable components by significant values. For example, the core temperature of the 33 kV cable is reduced by 15.6°C, while for the 66 kV cable, the cable core temperature is decreased by 12.6°C, and for 220 kV the conductor temperature is reduced from 71.3°C to 58.3°C when each cable is loaded by its rating.

Characterization of a novel TORT cable wound of stabilized striated REBCO tapes for reduced magnetization AC losses

REBCO (rare-earth barium copper oxide) high-temperature superconducting tapes, have a high potential for winding of large magnet coils. Tapes on round tube (TORT) cables represent a promising option for achieving a conductor suitable for the winding of magnet coils. However, certain applications, such as accelerator magnets, require the use of superconducting cables with low magnetization alternative current (AC) losses. There are several methods to reduce AC losses in TORT cables. Our first approach was to get rid of eddy currents by replacing the copper former with dielectric materials based on polymers and composites, i.e. polyethylene terephthalate glycol-modified reinforced with carbon fibers. Additional reduction of hysteretic loss was achieved by striating of copper coated REBCO tapes. We employed chemo-mechanical striating, for these objectives. However, the superconductor is exposed during the striating process, which may lead to later moisture-related degradation. Hence multilayers based on Ti/AlN were deposited using magnetron sputtering in order to protect the superconductor immediately after the striating process from water and atmospheric moisture corrosion. Subsequently, striated tapes as well as the non-striated tapes were then wound onto formers with diameters of 10 mm, 7 mm and 5.5 mm, and then on the short TORT cables bending tests were performed. After each technological step, direct current measurements were performed on the samples and finally the AC losses were measured.

Study on the Effect of Anchor Cable Prestress Loss on Foundation Stability

Anchor cable prestressing is one of the key factors in maintaining the stability of the supporting structure and controlling ground deformation. In order to further understand the influence of anchor cable prestress loss on the stability of the foundation pit, an underground station pit of Qingdao Metro Line 6 is taken as the engineering background, and numerical simulation research is carried out by using FLAC3D, which calculates the surface settlement, the deformation of enclosing piles, the support axial force, and the axial force of anchor cables in the process of excavation of the foundation pit and compares it with the on-site monitoring data, to get the law of the impact of prestressing force on the stability of the foundation pit in order to provide a reference for the design of the soil–rock Combined pit support system design and engineering construction to provide reference.

High-performance MTM inspired two-port MIMO antenna structure for 5G/IoT applications

Abstract This study thoroughly investigates a two-port multiple-input multiple-output (MIMO) antenna system tailored for 5G operation at 28 GHz. The proposed antenna is patched on a Rogers (RT5880) substrate with a relative permittivity of 2.2 and total size of 20×12×0.508 mm3. The mutual relationship between the radiating patches is refined using an H-shaped metamaterial structure to reduce the isolation to –55 dB. A MIMO configuration with attractive features is employed to reduce the envelope correlation coefficient (ECC) to about 0.00062 and the channel capacity loss (CCL) to about 0.006 bits/sec/Hz, while magnify the gain to about 9.39 dBi and the diversity gain (DG) to about 9.995. Additionally, it boasts a compact size with stable radiation pattern. The simulations of the MIMO antenna are executed using CST microwave studio, subsequently validated with Advanced Design System (ADS) for an equivalent circuit model, then measured using Vector Network Analyzer. Discrepancies between measured and simulated results were analyzed, with observed variations attributed to cable losses and manufacturing tolerances. Despite these challenges, a comprehensive comparison with prior research highlights the notable advantages of the proposed design, positioning it as a compelling solution for 5G applications.

Fiber to the home (FTTH) activation system and analysis of dropcore cable connection losses on optical network performance

Fiber to the home (FTTH) activation system and analysis of dropcore cable connection losses on optical network performance

Selection of an Optimal Frequency for Offshore Wind Farms

Offshore wind power has attracted significant attention due to its high potential, capability for large-scale farms, and high capacity factor. However, it faces high investment costs and issues with subsea power transmission. Conventional high-voltage AC (HVAC) methods are limited by charging current, while high-voltage DC (HVDC) methods suffer from the high cost of power conversion stations. The low-frequency AC (LFAC) method mitigates the charging current through low-frequency operation and can reduce power conversion station costs. This paper aims to identify the economically optimal frequency by comparing the investment costs of LFAC systems at various frequencies. The components of LFAC, including transformers, offshore platforms, and cables, exhibit frequency-dependent characteristics. Lower frequencies result in an increased size and volume of transformers, leading to higher investment costs for offshore platforms. In contrast, cable charging currents and losses are proportional to frequency, causing the total cost to reach a minimum at a specific frequency. To determine the optimal frequency, simulations of investment costs for varying capacities and distances were conducted.

Research on Identification Method of Cable Cross-Sectional Loss Rates Based on Multiple Magnetic Characteristic Indicators

Research on Identification Method of Cable Cross-Sectional Loss Rates Based on Multiple Magnetic Characteristic Indicators

The Garber Current Pattern: An Additional Contribution to AC Losses in Helical HTS Cables?

The Garber Current Pattern: An Additional Contribution to AC Losses in Helical HTS Cables?

Analysis of Power and Voltage Losses in Electric Submersible Pump Motor Installations

In area mining are quite extreme, where the level of safety from high temperatures and toxic gases which are explosive as well as well flow pressure is also high and can damage production equipment. Therefore, it is very necessary to install reliable electrical power, starting from analyzing the selection of cable types that used, voltage drop, power losses and transformer selection. The problems mentioned previously, this research carried out an analysis of improvements to voltage drops and power losses that occurred in the ESP motor installation system. The method used is to replace the type of cable used in three scenarios with three different types of cable. The installation system data obtained from this company was then processed using software which was then validated with theoretical calculation results. The result of voltage drops and power losses in ESP cables according to standards using scenario 3, replacing AWG 2/0 type with a voltage rating of 5 kV, diameter of 11.709 mm and has a KHA of up to 210 A. The voltage drop value after repairs are carried out based on theoretical calculation results has an average percentage index value of 4.5% and power losses of 4.6%. This shows that in the condition after repairs, both the results of simulation calculations and theoretical values have met the IEEE std 141-1993 standard which states that the value of voltage drop and power losses in industrial plan distribution systems must be below 5%.

Research on H-3K Creep Coupling Calculation Model of Long-Term Prestress Loss of Anchor Cables

Research on H-3K Creep Coupling Calculation Model of Long-Term Prestress Loss of Anchor Cables

Network losses with photovoltaic and storage

Recent development of dispersed generation technologies employing sustainable energy resources has encouraged the entry of power generation at distribution level. The close distance between load and generation reduces the network losses. However, DG system with electronic devices gives harmonic distortion. Harmonics introduce additional losses and could cause premature ageing as well as earlier re-investment of network components. This paper examines the network losses of a grid-connected photovoltaic (PV). The fundamental and harmonic losses of main network components, including transformer and cables, are calculated and compared among three cases: 1) without PV, 2) with PV, and, 3) with PV and storage.